ABOUT THE COVER
Epigenetic control of cellular polarity has recently come under scrutiny as a potential driver of tumorigenesis and progression. The cover shows a whole mount immunofluorescence image of an intestinal cell organoid in which the scaffold protein Dlg1 had been disrupted (green: phalloidin; red: lysozyme; blue: DAPI). Loss of Dlg1 does not affect the cells' ability to maintain polarity, but rather causes improper orientation of the mitotic spindle and loss of planar cell division, causing increased dwelling time in intestinal crypts. The authors suggest that delayed exit from the crypts allows for additional time to accumulate and retain mutations without increasing the overall mutation rate, thus contributing to a “tumor-permissive” environment in the intestine. Please see the article by Young and colleagues (beginning on page 686) for more information.